gistfile1.js

$(document).ready(function(){
  var focus = true;
  var count = 0;
  var title = document.title;

  $(window).focus(function(){
    focus = true;
    count = 0;
    setTimeout(function(){
      document.title = title;
    }, 500);
  });

  $(window).blur(function(){
    focus = false;
  });

  var pusher = new Pusher('your_api_key');
  var channel = pusher.subscribe('messages');

  channel.bind('messages', function(data){
    $('#messages').prepend(data); // specific to your app

    if (focus == false) {
      count++;
      setTimeout(function(){
        document.title = '(' + count + ') ' + title;
      }, 500);
    }
  });
});